I’ll describe experiments in very high time and space resolution by means of two extremely fast photometers (named respectively Aqueye and Iqueye) conceived with the aim to exploit properties of light not yet common in astronomical observations. The final goal is a ‘quantum’ photometer for extremely large telescopes (like the ESO E-ELT) capable to detect and measure second order correlation effects in the photon stream from celestial sources (according to the description of the EM field by Roy Glauber, 2005 Nobel Prize for Physics)
Very high time resolution: our photometers can tag the arrival time of each photon with a resolution of 25 picoseconds and accuracy of few hundred picoseconds for hours of continuous acquisition, and with a dynamic range of more than 6 orders of magnitude. Results obtained on optical pulsars will be presented in detail, but the photometers have been used also for lunar occultations, exo-planet transits and fast variable objects.
Very high space resolution: among the second order effects is intensity interferometry, known also as Hanbury Brown - Twiss Intensity Interferometry. Our tests with Aqueye and Iqueye give hope to perform very high spatial resolution observations among telescopes not optically linked, e.g. two or more unit of the ESO VLT, or Cerenkov light telescopes such as Magic or the future Cerenkov Telescopes Array (CTA).